The sticklebacks are small fish that are found in lakes and streams, brackish systems and in the ocean. Unlike most other fishes, sticklebacks take a cavalier attitude toward salinity; a single species will often reside in fresh, brackish and marine systems. They are distinctive fishes with highly protrusible mouths, narrow caudal peduncles, and few, if any scales on their bodies. If present, scales are often modified into ornate plates. There are few species in this family, but they are present throughout the northern hemisphere. In New York, one species is strictly freshwater and is present in most drainages. Another species is estuarine and found only in the Hudson River. The remaining species are found in fresh and brackish water and in the ocean. All are native to the state. The freshwater populations of the marine species have extremely limited ranges.